The nocturnal phenomenon of milky seas, explained by science

pictured here is the ocean at night. Scientists have been exploring a rare phenomenon whereby the ocean turns a luminous colour, called milky seas

For centuries, a rare nocturnal phenomenon has occurred called 'milky seas'. Image: Unsplash/Lukas Robertson

Steven D. Miller
Professor of Atmospheric Science, Colorado State University
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The bioluminescence in milky seas is caused by a type of bacteria. Image: Steve. H. D. Haddock/MBARI, CC BY-ND
an image showing a milky sea event off the east coast of Somalia
Researchers found a milky sea event off the coast of Somalia, seen here as a pale swoosh in the top left image. The other panels show sea surface temperature, ocean currents and chlorophyll. Image: Steven D. Miller/NOAA

this image shows a milky sea off the coast of Java which was the of Kentucky and lasted for more than a month
This milky sea off the coast of Java was the size of Kentucky and lasted for more than a month. Image: Steven D. Miller/NOAA
these are satellite images showing milky seas
The two images of milky seas on the left were taken with older satellite technology while the images on the right show the high-definition imagery produced by the Day/Night Band sensor. Image: Steven D. Miller/NOAA

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OceanScienceSDIS2021Climate Change
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